Spark-plug.



I Patented July 2, 1912.

SPARK PLUG.

APIPLIUATION FILED MAR, 10, 1911.

G. C. DAVIS.

fi ht Memos. M QM 40 I dust, or the like becoming de'posited thereon the sparking point of the transmitting wirev Tolazl whomjg 6 NITED sTA Es-rn E T orrion. 1

eaovnn c. mvrsg or NEW YORK, N. .Y.

SIRARK-PLUG.

, Be it known that" 1, ammo. ns e I citizen of the United States, and zit-resident .of New York, borough of Brooklyn, county of Kings, and State of New York,'have invented' certain new and. useful Improvenients in Spark-Plugs, of which the follow 'ing is a fllllyClGfLI', and'exactspecification.

This invention relatesto a class of devices or spark plugs adapted for use in conjunction with the operation of combustion en gine'sy I -My invention for'its object primarily to provide a form of spark plug designed for use in connection with the compression chamber-of a combustion engine for exploding the charges ofgaseous fuel admitted thereto and which may be conveniently ad'- justedwithout removal from the engine for changing the electric contact points so as to.

effectually clear the contact points of all deposits of non-conducting electric prodinsulated transmitting Wire" carrying upon one end thereof a plurality of sparking points which are adapted to be movedsuccessively so as to provide a-spark gap between each o-f'said sparking points and a' sparking point provided upon the casing so that in event of oil, carbonaceous substances,

in register with the sparking point of the casing may be replaced-with another point by revolving saidtrans'mitting wire. Y 1

Another object of the invention is. to provide a .device' or means adapted to manually rotate -the. insulated transmitting wire {to predetermined positions whereby a positive register ofthe sparking points thereof with the'sparkmg point of the casing will be in- I 'sured 'atall tim'es;.'a'nd a further object'of the invention'is to provide a spark plugof compact form and asimplified arrangement 1 arts. which zlnay befreadily agsseijllbled made" durable.

Specification of ietters Patent. i Applicati'cin filed March 10, 1911.

Serial No. 613,620.

panying drawing, which forms a part of this specification, and will then be pointed out in tion. V

In thedrawing, Figure 1 is an elevationof one form of spark plug embodying my invention. Fig. 2 is a top plan, partly in sec- PatentedJu1y2,.1912.

' 'With these and other objects view, the I invention will be hereinafter more particularly described with reference to the accomthe claims at the end of the descripr tion, of the spark plug. Fig. 3 is an inverted plan of the bottom of the spark plug, and

Fig. 4 is a. section taken on the line II II of Fig. 1. I

The spark plug'lO has a tubular casing 11 havingits lower end exteriorly threaded, at 12, so as to be screwed ina threaded opening of any suitable part of the wall of the compression. chamber of a combustion engine. The end of the tubular casing 11 opposite to the threaded end l2'th'ereof is circumferentially cut-out or'reduced, as .at 13;

in order to providean annular shoulder 14. Interiorly of the threaded end 12 of said tubular casing is an annular band orfflange 14 andupon the under surface of the threaded end is a projecting sparking .point 15.

Through the tubular casing 11'is disposed a transmitting. wire 16 which is embedded in an insulating post 17 extending some distanc'eabovefithe tubular casing, and said.

transmitting wire is of greater length than the insulating post so as to extend beyond both ends thereof, as shown.

Upon the end of the transmitting'wire 16 extending beyond. the end of the insulating post 17 at the threaded end of the tubular casing 11 is provided a plurality ofspark ingpoints, as 18. I prefer to employ six ofthe sparking, points 18 and arrange said points in the shape of a six-arm star so'that every two sparking points thereof will be disposed diametrically opposite to each other. The-opposite end of the transmittin threaded end is a cap or'binding post 20 to which is. held an arm 21 having aclip.22

provided upon the opposite end thereof.

'The'clip'22 adapted to connect the ar'm1'9' T wire 16 is threaded, as M319, and upon sai tothefwire leading from one pole of the usual or any preferred type of storage-bat-v l I 'tery while the wire leading from the other.v

pole of'the storage battery maybe connected i 110.

in any suitable manner so asfto' provide an electric circuit through the-clip '22, over the arm I21, :through the transmitting wirepltj rotating and-through one of the sparking points 18. At the same time the current of electricity will pass from the other pole of the storage battery through the tubular casing 11 .to the sparking point '15 thereof.

About midway of the insulating post 17 is projectin annular flange 23 against which rests one edge of a jacket 24 which extends around said insulating post: to the end of the threaded end of the tubular casing 11 and terminates with an exterior annular band or flange 25 which abuts against the annular band or flange 14 interiorly of said tubular casing. By forming thejacket 24 and the tubular casing 11, as described and illustrated, concentric recess 26 is provided between the inner surface of said casing and the outer surface of the jacket. The end of the jacket 24 opposite to the annular flange 25 is exteriorly threaded, as at and upon said threaded end of the jacket is held the annular ring or flange 28 of the' ratchet 29 of a device 30 which is adapted to rotate the jacket 24 and simultaneously "therewith revolve the insulating post 17 for the transmitting wire 16 so as to adjust the sparking points 18 whereby one uppn the insulating post 17 and underneath a pi of said sparking pomts when moved will clear the sparking point 15. of the tubular.

casing 11 hf all deposit thereon of oil or t proper generating of sparksvbei C. points. i I

a ratchet 29 of the ns 30 is circular in form and proporately larger in diameter than the circumference of the sparking" points 18, and in the peripheral edge of the ratchet 29 is formed a plurality of notches 31 which are of equal number to the sparking points 18 and are spaced apart at intervals so that when revolved the transmitting wire 16 will be rotated to move one of the sparking foreign substances which may tend adjusting device or points 18 in register with the sparking point,

1.5 of the-tubular casing 11. In order to manually rotate the ratchet 29 I provide t -het 29 a movable plate 32 which has ,cting part 33, and upon one surface of said projecting part is pivoted a lever 34. The lever 34 has a handle 35 by which said lever may be manually moved, and projecting from one edge of the pivoted end thereof is a toe 3G. edge of the pivoted the a end of the lever 34 is pivotally held upon the projecting part 33 of the movable plate 32 a 'dog 37 which adapted to engage one of the notches 31 of the ratchet 29, and to said dog is held one end of a spring 38 which has its other end engaging the edge of t e pivoted end of the lever 34 so as to orma ly serve to hold the .dog in contact wi h the ratchet 29. Between the movable plate 32 and the annular shoulder 14 of the tubu lar casing 11 is rigidly In proximity to the opposite and upon 40. In the path of movement of the toe 3(3 of the lever 34 and at one edge of the rigidly held plate 39 is pivoted one end of an arm 41 of a pawl 42. Projecting substantially at a right angle from one edge of the arm 41 orthe-pawl 42 is a tooth 43 which is adapted to engage one of the notches 31 of the ratchet 29 so as, to 'prevent'said ratchet from movement when in. engagement therewith,

the end of the arm 41 opposite to its pivoted end' is a finger -44'one edge of which-is adapted to be engaged by the toe 36 of the'lever 34 so as to swing the pawl 42 in a direction, as indicated by dotted lines at 45, for, freeing the engagement of the tooth 43 from one of the notches 31 of the ratchet 29' when said lever is moved in a direction, as shown by dotted lines at 46. To the pawl 42 is held one end of a spring 47 the other end of which is fastened upon the rigidly held plate 39 and said spring serves to force the pawl 42 so that the tooth 43 thereof will normally engage one of the notches 31 of the ratchet 29. Encircling the acket 24 of the insulating post .17 and within the concentric recess 26 is arranged a spiral spring vent the inner jacket 24 and the insulating post 17 from being forced from the tubular casing 11 by the suction created in the compression chamber of a combustion engine by the alternate movement of the piston thereof. As illustrated, when the lever 34 is moved to the position, as shown by the dotted lines 46, the toe 36 thereof will guide the finger 44 of the pawl 42 so as to release the engagement of the tooth 43 with one of the notches 31 of the ratchet 29. The plate 32 will thereby be moved and simultaneously therewith the dog 37 will force the ratchet to rotate the insulatingvpost 17 for revolving the transmitting wire 16 at which time one of the sparking points 18 will be posi tio'ned soas to register with the'sparking point 15 of the tubular casing 11 for continuously generating electric sparks between said points.

In the foregoing description I have embodied the preferred form of my invention, but Ido not wish to be understood as limiting myself thereto, as I am aware that modifications may be made therein without departing from the principle or sacrificing any of the advantages'of this invention, therefore I reserve to myself the right to make such changes as fairly fall within thescopc thereof.

llaving thus described my invention, I

claim as new anddcsire to secure by Let? 48 normally serving to preexteriorly threaded and having its opposite y orid one end thereof; a transmitting wire embedded in the insulating post; said transmitting wire being of greater length than the-insulatingpostso as to extend beyond. foflsparking points provided upon the end o'f the'transmitting wire at the threaded end hfthe tubular casing; means provided uponteriorlyl "threaded gr tingi "end exteriorly reduced, said tubular casing having an annular band formed interiorly .'-of its threaded end and having a sparking point projecting from the underside of-its threaded end; of an inner jacket-rotatable within the tubular casing. and abutting against the annular band of said casing; aninsulatingpost held within the jacket and I rotatable therewith, said post project-ing be fm'yond one end thereof; atransmitting wire embedded inthe insulating post, said trans- -mitting wire being" of greater length then the insulatingpost so. as to extend beyond I the ends of'saidinsulating p'0st;-a plurality of'sparkin'g" points provided upon the endof the transmitting wire at the threaded end of the tubular casing;'me ans provided upcn the opposite end of thetransmitting text'eriorly threaded and having its opposite 30 formed interiorly of the threaded end of end exteriorly reduced; 'anannular band jthe tubular casing; a sparking point projecting from'the underside of said threaded end; of an inner jacket rotatable within the tubular casing and having an annular band formedzexteriorly at one end thereof where- ;by 'a"ooncentric recess is provided between said inner jacket and the interior surface of the tubular casing; an insulating post held within the jacket and projecting betheends of said insulating post; a plurality "the opposite end'of the transmitting wire and adapted to connect said wire to a -storrage battery; a device provided upon'the tubular casingand adapted when moved to rotate the insulating post for revolving 'the the sparking points of theitransmitting wire h the sparking point o f'saidtubular cas 11g; and a spiral springeneircling the jacket to retain saidjacket and 'the in'sulating post within thetubularicasingagainst lacem'ent-bythesuction created by the pis en 0f a combustion engine. I

,.' a spark plug ;the cornbi at-i0 bnlar casing having 'oneiendex transmitting wire so as -to register one'of 5;.

t e' insulatingpost and-- normally- -ser v.

'endenteriorlyreduced, said tubular casing having an annular band formed interlorly of its threaded end and having a sparking threaded end; of an innerjacket rotatable within the, tubularcasing and having an annu ar band formed -exteri'orly at one'end 'point projecting from theunderside of its thereof and abutting against theannula-r band of the tubular casing whereby a con-' centric recess is provided between said inner jacket and the interior surface of the-tubu- -lar casing; an insulating post held within the tubular. casing and projecting beyond one end thereof; a transmitting wire embedded-in the insulating post, said transmitting wire being of greater length than the insulating post so as to extend beyond the ends of said insulating p0st; a pluralityl i of sparking points :provided upon the end of the transmitting wire at the threaded end of the tubular easing; means provided upon the opposite end ofthe transmitting wire and adapted to connect said wire to a storage battery; a ratchet provided upon the insulating post and having an annular flange connected to said inner jacket; a movable plate provided upon the insulating post between the'ratchet and the rigidly held plate of the tubular casing means provided upon the movable plateand adapted when moved to rotate the ratchet and the insulating post for revolving the transmit-- ting wire so as to register one of the spark-. ing points of the transmitting wire with sparking point of said tubular casing; and a spiral spring encircling the jacket of the insulating post and normally serving to retain said jacket and the insulating post within the tubular easing against displacement by the suction created by the' piston of a combustion engine.

4:. Ina p k P he combination 'wit-h I endexteriorly reduced so as to provide, an

annular shoulder, said. tubular casing hav-- ing arr-annular band formed interiorly of a tubular casing havingone end thereof ex- '3 teriorly threaded and having its opposite its threaded end and having a sparking point projecting from the underside of its threaded end of an inner jacket rotatable within the tubular casing and having anEa-nn'ulart' band formed exteriorly at one end thereof; and vabutting against the annular. I handof. the tubular casing whereby a' concentric recess is, provided betweenlsaidmner acket and-the interior. 'surface*o'f the tubular I casing an insulating post'held within the tubular casingjandfp fojeoting' beyond one end'thereof;aitransmittingwire embedded h theinsulating peed-said transmitting wire'being of greater length than the insu- :lating post so as to .extendbeyond the ends of said insulating'post; a plurality of spark; ing p'oints provided nponjthe end of the a pe e:

e fingwi eet the eman te oflthe tubular casing; means provided upon the opposite end of the transmitting wire'and adapted to connect said wire to as'torage battery; a plate rigidly held upon thearednced end of the tubular casing; a ratchetprovided upon the insulating post and having an annular flange upon one'surface thereof, said annular flange being connected 'to the inner 'jacket; a movable plate provided upon the insulating post between the ratchet and the rigidly held plate of the tubular casing; a dog pivoted upon the movable plate and adapted to engage the ratchet; a pawl pivotally held upon the rigidly held plate and adapted to also, engage the ratchet; means provided upon the movable plate and adapted when moved to swing said pawl from engagement with the ratchet whereby said ratchet will be moved to retate the insulating postfor revolving the transmitting wire so as to register one of the sparking points of the transmitting wire with the sparking point .of said tubular cas-v ing; and a spiral spring encircling the jacket of the insulating post and normally. serving to retain said ack'et and the insulating-post within the tubular casing against displacement by the suction created by the piston of a combustion engine.

5. In a spark plug; the combination with a tubular casing teriorly threaded and having its opposite end exteriorly reduced so as to provide an annular shoulder, said tubular casing; having an annular band formedinteriorly of its threaded end and having a sparking point projecting from the underside of its threaded end; of an"inner jacket rotatable within the tubular casing and having an annular band formed exteriorly at one end thereof and abutting against the annular-band of the tubular easing whereby a concentric recess is provided between said inner jacket and the interior surface 'of the tubular casing; an insulating post held within the tubular casing and projecting beyond one end thereof; a transmitting wireelnbedded in the insulating post, said transmitting wire beihgof greater length than the insulating post so as to extend beyond the ends of said insulating post; a plurality of sparking points provided-upon the end of the trans mitting wire at the threaded end of the tubular casing; means provided upon the opposite end of the transmitting wire and adapted to connect said wire to a storage battery; a plate rigidly held upon the re- .dnccd end of the tubular easing; a ratchet provided upon the insulating post and having an annular flange upon one surface thereof; said annular Ilange being connected to the inner jacket; a movable plate provided upon the insulating post between the ratchet and the rigidly held plate of the tubular casing; adog pivoted upon the movhaving one end thereof eX- able plate and adapted to engage the ratchet; a pawl pivotally held upon the rigidly held plate and adapted to also engage the ratchet; a lever provided upon the movable plate and adapted when moved to swing said pawl from engagement with the ratchet whereby said ratchet will be moved to rotate the insulating post for revolving the transmitting wire so as to register one of the sparking points of the transmitting wire with the sparking point of said tubular casing; and a spiral spring encircling the jacket of the insulating post and normally serving toretain said jacket and the insulating post within the tubular casing against displacement by suction created by the piston of a combustion engine.

6. In a spark plug; the combination with a tubular easing having-one end thereof exteriorly threaded and having its opposite end exteriorly reduced so asto provide an annular shoulder, said tubularcasing having an annular band formed interiorly of its threaded end and having a sparking point projecting from the underside of its threaded end; of an insulating post rotatable within the tubular casing and projecting beyond one end thereof a transmitting wire embedded in the insulating post. said transmitting wire being of greater length "than the insulating post so as to extend beyond the ends of said insulating post; a plurality of sparking points provided upon the end of the transmitting wire at the threaded end of the tubular casing; means provided upon theopposite end of the transmitting wire and adapted to connect said wire to a storage-battery; a plate rigidly held upon the reduced end of the tubular casing: a. ratchet provided upon the insulating post and having a plurality of notches providedin the peripheral edge thereof; a plate movably held upon the insulating post between the notched ratchet and the rigidly held plate of the tubular casing; a dog pivoted upon the movable plate and adapted to engage one of the notches of the ratchet; a spring provided upon the dog and normally serving'to force said dog into engagement with one of the notches of the ratchet; an arm having one end pivoted upon the rigidly held plate: a finger formed upon the opposite end of the arm; a tooth formed upon one edge of the arm and adapted to engage one of tho notches of the ratchet; a spring having one end held to the arm and having the other end thereof held to the rigidly y .held plate; said spring nb rmally servlng to force the tooth of the arin into engagement with one of the notches oi'j/the ratchet; and a lever having one of its ends jivot'ed to the movable plate adjacent to the og, said lever having a toe formed upon the edge. of the pivoted end thereof and adapted tip-swing the finger of the arm so as, to free the tooth teriorly threaded and having its opposite f' one endthereof; a transmitting wire emheld plate; a finger formed upon the .oppo

v ivoted to the movable plate adjacent to the a 9 of said arm from engagement with the notch of the ratchet whereby said ratchet may be moved to rotate the insulating post .for revolving the transmitting wire so as to register one of the sparking points of the transmitting wire with the sparking point ofj said tubular casing. 3

. 7. In a spark plug; the'combination with a tubular casing having one end thereof exend exteriorly'reduced so as to provide an annular shoulder, said tubular casing having an annular band formed interiorl of its threaded'end and having a spar ing. point projection from the underside of its threaded end; of an inner jacket rotatable within the tubular casing and having an annular band formed exteriorly at one end thereof and abutting against the annular hand of the tubular casing whereby a concentric recess is provided between said inner jacket and the interior surface of the tuhular casing; an insulating post held within the tubular casing and projecting beyond bedded in the insulating post, said transmitting wire being of greater length than the insulating post so as to extendbeyondthe? ends of said insulating post; a pluralit of sparking' oints provided upon the end of the transttting wire at the threaded end of the tubularfea sing; means provided. upon" the opposite end "(if the transmitting wire and'adapted to connect said wire to a 'stor?" age battery; a'plate ri 'dly held upon the reduced end of the tubu ar casing; a ratchet provided upon the insulating postand havng a plurality of notches provided in the peripheral edge thereof; a platefmfovably 40 held upon the insulating post between the notched ratchet and the rigidly held plate of the tubular casing a dog pivoted upon the movable plate and adapted'to engage onevof the notches of the ratchet; a spring provided upon; the dog and normally serv mg to force sald dog into engagement with one of the notches of the ratchet; an arm having one end pivoted upon the, rigidlysite-end of the arm; a tooth formed upon one edge of the arm and adapted to also engage one of the notches of the atchet; a

' spring having one end held to th; arm and having the other end thereof held 0 the rig-' idly held plate, saidsp'ring normally serving to force thetooth of the arm into en- 'gagement withone of the notches-of the ratchet; and a lever having one of ends 0g, said lever having a toe formed upon the edge-of the pivoted end thereof and adapted when moved to swing the fingerof the arm "so as to free. the tooth of said arm from engagement with the notch of the ratchet 'end exteriorly reducedfso as to provide annotches provided in the peripheral edge "thereof; a plate 'movabl held upon the insulating post between t and the rigidly held plate of thetubular cas- "ing; a dog pivoted upon the movable plate and adapte ratchet; an arm having one end pivoted ved to also engage one of the notches of the' volving the transmitting wire so as to regiswhereby said ratchet may be movedto r0- tate the insulating'post forrevolving the transmitting wire so as tov register one of the sparking points of the transmitting wire.

with the sparking point of said tubular casing; and a spiral spring encircling the jacket of theinsulating post and normally serving to retain said jacket and the insulating post'within the tubular casing against displacement by suction created by thelnovement, of the piston of a combustion eng1ne."' 8. In a spark plug; the combination with a tubular casingliaving one endthereof ex- I teriorly threaded and having its opposite annular shoulder, said tubular. casing havlng a s arkingpoint projection from the undersi e of, its threaded end; of an insulating post rotatable within the tubularcasing and projectingbeyond one end thereof; 'a

a 85.. transmitting wire embedded in the insulating post, said transmitting wire being oi"v greater length than the insulating post so as to extend beyond the ends of said insulating post; a plurality of sparkingpoints provided upon the end of t e transmittin wire at the. threaded end of the tubular casing; a p

' ate ri 'dly held upon the reduced end of he tuhfi 'ar casing; a ratchet provided upon the insulating post and having a plurality of notched ratchet to engage one of the notchesof the ratchet; a spring provided upon the dog and normallyserving to force said dog into engagement with one' of the notches of the upon the rigidly'held plate; a' finger .formed upon theopposite end of the arm; a tooth formed upon one edge of-the arm'and adaptratchet; a spring having one end held'to the I arm and having the other end thereof heldto the rigidly held plate, said spring nor-, v mally serving to force the tooth of the arm into engagement withone of the notches of Y the ratchet; and a lever having oneof its ends pivoted to the movable plate adjacentto the dog, .s'aid leverhaving a toe formed upon the edge of the pivoted end thereof and adapted when manually moved to swing the finger-of the arm so as to free the tooth of said arm fromengageme'nt with the notch of the ratchet whereby said ratchet may be moved to rotate the insulatingpost for 're- 'ter one of the sparking points of the.'trans-' mitting Wire with the sparking point of said tubular casing. f

9. In a spark plug; the combination with a tubular casing having one emf thereof ex-' teriorly threaded and having its opposite 180 annular shoulder, said'tubular' casing having a sparking point projection from the underside of its. threaded end; of an insulating post rotatable within the tubular casing and projecting beyond one end thereof; a transmitting wire embedded in the insulating post, said transmitting wire being of greater length than the insulating post so as to extend beyond the ends of said insulating post; a plurality of sparking points provided upon the end of the transmitting wire at the threaded end of the'tubular casing; a plate rigidly held upon the reduced end of the tubular casing; a ratchet provided upon the insulating post 'and having a plurality of notches provided in the peripheral edge thereof; a plate movably held upon the insulating post between the notched ratchet and the rigidly held plate of the tubular casing; a dog pivoted upon the movable plate and adapted to engage one of the notches of the ratchet; a spring provided upon the dog and normally serving to force said dog into engagement with one of the notches of the ratchet; a pawl having one end pivoted upon the rigidly held plate; a finger formed upon the opposite end of the pawl; a tooth formed upon one edge of the pawl and adapted to also engage one of the notches of thereofand adapted when manually moved to swing the finger of the pawl so as to free the tooth 'of said pawl from engagement with the notch of the ratchet whereby said ratchet may be moved to rotate the insulating post for revolving the transmitting wire so as to register one of the sparking points of, the transmitting wire with the sparking point of said tubular casing; and a spring arranged around the insulating post and normally serving to retain said insulating F post within the tubular casing against displacement by suction created by the movement of the piston of a combustion engine.

This specification signed and witnessed thisnint'h day of March A. D. 1911.

GROVER C. DAVIS.

Witnesses ROBT. B. ABBOTT, E. M. J ERKE. 

